1 files changed, 94 insertions, 0 deletions

diff --git a/unit_tests/scripts/coro/basics.lua b/unit_tests/scripts/coro/basics.lua
new file mode 100644
index 0000000..4444e87
--- /dev/null
+++ b/unit_tests/scripts/coro/basics.lua
@@ -0,0 +1,94 @@
+local lanes = require "lanes"
+
+local fixture = require "fixture"
+lanes.finally(fixture.throwing_finalizer)
+
+local utils = lanes.require "_utils"
+local PRINT = utils.MAKE_PRINT()
+
+if true then
+    -- a lane body that just returns some value
+    local lane = function(msg_)
+        local utils = lanes.require "_utils"
+        local PRINT = utils.MAKE_PRINT()
+        PRINT "In lane"
+        assert(msg_ == "hi")
+        return "bye"
+    end
+
+    -- the generator
+    local g1 = lanes.coro("*", {name = "auto"}, lane)
+
+    -- launch lane
+    local h1 = g1("hi")
+
+    local r = h1[1]
+    assert(r == "bye")
+end
+
+-- a lane coroutine that yields back what got in, one element at a time
+local yielder = function(...)
+    local utils = lanes.require "_utils"
+    local PRINT = utils.MAKE_PRINT()
+    PRINT "In lane"
+    for _i  = 1, select('#', ...) do
+        local _val = select(_i, ...)
+        PRINT("yielding #", _i, _val)
+        local _ack = coroutine.yield(_val)
+        assert(_ack == _i)
+    end
+    return "done!"
+end
+
+if true then
+    -- if we start a non-coroutine lane with a yielding function, we should get an error, right?
+    local fun_g = lanes.gen("*", {name = "auto"}, yielder)
+    local h = fun_g("hello", "world", "!")
+    local err, status, stack = h:join()
+    PRINT(err, status, stack)
+    -- the actual error message is not the same for Lua 5.1
+    local msgs = {
+        ["Lua 5.1"] = "attempt to yield across metamethod/C-call boundary",
+        ["Lua 5.2"] = "attempt to yield from outside a coroutine",
+        ["Lua 5.3"] = "attempt to yield from outside a coroutine",
+        ["Lua 5.4"] = "attempt to yield from outside a coroutine"
+    }
+    local expected_msg = msgs[_VERSION]
+    assert(err == nil and status == expected_msg and stack == nil, "status = " .. status)
+end
+
+-- the generator
+local coro_g = lanes.coro("*", {name = "auto"}, yielder)
+
+if true then
+    -- launch coroutine lane
+    local h2 = coro_g("hello", "world", "!")
+    -- read the yielded values, sending back the expected index
+    assert(h2:resume(1) == "hello")
+    assert(h2:resume(2) == "world")
+    assert(h2:resume(3) == "!")
+    -- the lane return value is available as usual
+    local r = h2[1]
+    assert(r == "done!")
+end
+
+if true then
+    -- another coroutine lane
+    local h3 = coro_g("hello", "world", "!")
+
+    -- yielded values are available as regular return values
+    assert(h3[1] == "hello" and h3.status == "suspended")
+    -- since we consumed the returned values, they should not be here when we resume
+    assert(h3:resume(1) == nil)
+
+    -- similarly, we can get them with join()
+    assert(h3:join() == "world" and h3.status == "suspended")
+    -- since we consumed the returned values, they should not be here when we resume
+    assert(h3:resume(2) == nil)
+
+    -- the rest should work as usual
+    assert(h3:resume(3) == "!")
+
+    -- the final return value of the lane body remains to be read
+    assert(h3:join() == "done!" and h3.status == "done")
+end